6o 
Knight. — On the Use of the 
Fig. i. Effect upon the stomata of the continued passage of air. Begonia 
(‘ President Carnot’). 
Fig. 2. Effect upon the stomata of continued passage of air. Eucharis Mastersi. 
In addition to the above-mentioned stimulation, which partakes of 
the nature of a cumulative effect, there is the possibility that a change 
in the stomata may be produced immediately the air-stream begins to 
pass through a leaf, an effect which is unaltered by the continued appli- 
